Elbow is a commonly used connecting pipe fitting in installation, which is used for the connection at the bend of the pipeline and is used to change the direction of the pipeline.
Other names: 90° elbow, right-angle elbow, love and bend, stamping elbow, pressing elbow, mechanism elbow, welding elbow, etc.
Purpose: To connect two pipes with the same or different nominal diameters, so that the pipes can make turns of 90°, 45°, 180° and various degrees.
Bending radius less than or equal to 1.5 times the pipe diameter belongs to the elbow, and greater than 1.5 times the pipe diameter belongs to the elbow.
Technical requirements for the production of elbows:
It is required to control the radius of curvature. For example, if the radius length is 1.5D, then the radius of curvature must be within the required tolerance range. Since most of these pipe fittings are used for welding, in order to improve the welding quality, the ends are turned into bevels with a certain angle and a certain edge. This requirement is also relatively strict, such as the thickness of the edge, the angle and the deviation range There are regulations, and there are many more items in geometric dimensions than pipe fittings. The surface quality and mechanical properties of the elbow are basically the same as those of the pipe. For the convenience of welding, the steel material of the connected pipe should be the same.
1- 1.5 times the center height of the elbow A=diameter*1.524, which is actually the multiple of the diameter D*, the result obtained will be
The numbers after the decimal point are rounded to integers. For example, the diameter D of 219 is 200, and the center height is
200*1.524=304.8, take 305; for another example, the diameter of 114 is 100, and the center height is 100*1.524=15.4,
(The algorithm suitable for the curvature radius of DN100 and above elbows is convenient and quick to calculate).
2-Stamp height = center height + radius of the elbow, such as 1.5 times the height of the elbow with a diameter of 219 = 305 + 219/2 =
3-Outer arc length=(center height+radius)*3.14*2/360*degrees, ie (stamp height)*3.14*2/360*degrees,
From this, it can be calculated that the length of the outer arc of the 90-degree elbow = stamp height * 3.14/2
4-Inner arc length=(center height-radius)*3.14*2/360*degrees
5-The blanking length of the elbow = the height of the center of the elbow * 3.14/2 * the outer diameter of the elbow / the diameter of the pipe + (the wall thickness of the pipe * 3)
+ Machining allowance, such as cutting 180*8 pipes and pushing 273 elbows, can be calculated with the above formula,
Cutting length=381*1.57*273/180+24=931.22mm+machining allowance.